Fair Value Measurements (Details 2) (Embedded derivatives [Member])	12 Months Ended
Dec. 31, 2014
Unobservable inputs used by management in determining fair value of embedded derivatives
Risk margin for uncertainty in cash flows	0.52%
Minimum [Member]
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary's credit risk	0.40%
Surrenders	4.00%
Partial surrenders	2.00%
Annuitizations	1.00%
Deaths	1.50%
Budgeted option costs	2.25%
Maximum [Member]
Unobservable inputs used by management in determining fair value of embedded derivatives
Adjustment for insurance subsidiary's credit risk	1.75%
Surrenders	16.00%
Partial surrenders	6.00%
Annuitizations	1.50%
Deaths	3.00%
Budgeted option costs	3.50%

Risk associated with risk of annuitizations, expressed as a percentage, used as an input to measure fair value.

No definition available.

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- Definition

Risk associated with risk of budgeted option costs, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Risk associated with risk of deaths, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Risk associated with risk of partial surrenders, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Risk associated with risk margin for uncertainty in cash flows, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Risk associated with risk of surrenders, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Details

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- Definition

Risk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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